The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper investigates connecting renewable energy sources such as solar, wind and the others to the microgrids through power electronic interfaces for active power provision and also harmonic, unbalance, and reactive power compensation under both symmetrical and asymmetrical voltage sources. The four-leg converter topology is applied because of its better controllability in four-wire systems applications...
This paper introduces a new multi-functional double mode inverter (MFDMI) scheme, which is able to operate under a variety of operational conditions for aggregation of PV-based renewable energy resources. Detecting islanded situation within a new and fast approach, regulating the voltage in the islanded mode, smooth transition between islanded and grid-tied (GT) modes, injecting both active and reactive...
In this work a bi-level (Supervisory-Local) PV-based Microgrid configuration is proposed for low power residential applications. In the supervisory level a long-term control scheme is assigned to define the set points for local controllers. The local level is mainly formed from a set of controllers which are basically responsible to control the power electronic interfaces and converters. Within the...
This paper discusses the use of a Cascaded H-bridge Multilevel Inverter (CHMI) as shunt active power filter (SAPF) for selective disturbing currents compensation. The main feature of the proposed approach is the use of independent DC sources, with reduced DC-link voltages, which makes such a topology an ideal candidate for medium and high power applications with increased reliability. The developed...
The operation of an air-conditioning system, completely powered by geothermal energy, with no other external energy input and no heat pump is described in this paper. This geothermal system can contribute to the reduction of electricity consumption in residences and small businesses, and can retrofit any installation, since it is a surface geothermal energy installation. That is possible because soil...
This paper develops selective strategies for Neutral Point Clamped Multilevel Inverter (NPC) in a microgrid application with load current decomposition based on Synchronous Reference Frame (DQ) method. The 3-level NPC inverter is investigated as widely used topology for medium and high power applications. In addition to the current injection into the grid, the 3-level NPC DG inverter is also being...
This paper presents a 5-level Cascaded H-Bridge Multilevel Inverter (CHMI) able to perform several tasks and applicable to a microgrid with multiple local power sources. The current control strategy is based on the conservative power theory (CPT) generating references for different modes of operation. The primary merits of multilevel cascade voltage source inverters are the possibility of having independent...
A multitask Asymmetrical Cascaded H-Bridge Multilevel Inverter (ACHMI), suitable for microgrid systems with possible unbalanced and nonlinear loads, is presented. The primary advantage of ACHMI is to produce a staircase output voltage utilizing unequal DC voltages such as Solar cells, fuel cells, batteries on the individual H-bridge cells. The ACHMI provide a large number of output steps without increasing...
In order to address the power quality enhancement in a given microgrid, independent control of reactive, unbalanced and distorted load current components, in a multi-inverter-based approach may be required. Therefore, this paper proposes a coordinated control strategy using the Conservative Power Theory (CPT) and assuming the contribution of all grid connected interfaces, especially those related...
This paper presents a design framework for a power electronic interface for a grid-tied (GT) low voltage DC distributed generation (DG) with short transient recovery between GT mode and islanding mode. The proposed interface contains controlled unidirectional and bidirectional floating interleaved converters (FIC), in addition to a smart grid-tied inverter (GTI) to optimize the overall performance...
Fast and accurate identification and localization of power line outages is one of the critical issues for efficient monitoring and control tasks in future smart grids. In this work, considering the whole power network (PN) as a single graph, the recently introduced sparse formulation of the Power line Outage Identification (POI-SRP) is represented. Our main contribution is to improve and generalize...
This paper develops a flexible control strategy for DG inverters in a microgrid application with load current decomposition based on Instantaneous Power Theory (PQ). For grid connected mode of operation, the control strategy simultaneously supply all or part of the load current components allowing the DG system to inject its available energy, as well as to work as an active power filter, mitigating...
In multi-inverter-based islanded microgrids with unbalanced and distorted loads, due to voltage drop across line, the load bus voltage is unbalanced and distorted, which shows the requirement for power quality increase at load bus. To address this problem, this paper presents master-slave-based cooperative operation of DGs with the implementation of Conservative Power Theory (CPT), in which in addition...
The main goal of this paper is to design and analyze a bidirectional floating interleaved DC-DC buck-boost converter applied to a residential photovoltaic (PV) power system with energy storage. The floating interleaved bidirectional converter produces a higher DC voltage gain compared to conventional converters, reducing the required number of series connections for the PV and battery modules. This...
This paper presents a three phase grid connected DC/AC inverter with active and reactive power (VAR) control for medium size renewable and distributed DC energy sources. The inverter, based on a voltage sourced inverter (VSI) configuration, allows the local residential energy generation to actively supply reactive power to the utility grid, at the same time, this topology allows to work this installation...
This paper investigates three different control techniques for controlling shunt active compensators for harmonic, reactive power and unbalance compensation. The considered methods were the instantaneous real and imaginary power theory (PQ), the Conservative Power Theory (CPT) and the synchronous reference frame method (DQ). So, the major goal is to explore the main similarities and differences in...
This article discusses recent trends in Smart Grid technology. Three selected aspects are (1) distributed information technology (IT), used for smart metering and multi-agent based controls, (2) big-data, resulting out of metering, sensors and other IT-enabled sources of information, and (3) an intelligent demand side, where demand response serves as contribution to grid services. New elements in...
The transient performance of a small-scale plant consisting of a photovoltaic (PV) and a pumped hydro storage (PHS) system has been evaluated. An indirect field oriented control (IFOC) based state-vector pulse width modulation (SVPWM) drive connects the plant to the distribution system. The drive system includes two six-pulse IGBT converters interconnected through a DC link, to which the PV plant...
The use of power converter is becoming very popular nowadays to maximize the power extraction from wind as well as interfacing the wind generator with the power grid. LCL filter plays an important role for interconnecting the inverter to the utility grid. Although several researchers designed LCL filtering based inverters, it has been still lacking in the literature a consisted and systematic design...
This paper discusses the use of Multi-Agent- Systems to control various systems in a commercial building in order to achieve maximum energy efficiency while maintaining comfort for the occupants and allowing a possible interconnection with a smart-grid. An approximated optimal control is proposed in this paper, where on-line training of a Bayesian state-machine learns the system for a given utility...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.